The living space of your home can be expanded with the addition of a deck. When the weather is beautiful, your deck transforms into a bustling center of activity, making it the ideal location for hosting gatherings of friends and family members outside. Because the last thing you want is for your deck to be unsafe in any way, having a deck that is slippery can be an issue for you.
Read more: How to Build Deck Stairs & Ste
Why is My Deck Slippery?
As the seasons change, you will find that leaves and other debris have accumulated on your deck. The longer you wait to clear dirt particles off your deck, the longer moisture will stick around, providing the conditions for mold, mildew, algae, and moss to grow, which will cause the deck surface to become slippery. This may seem like a harmless occurrence at first, but the longer you wait, the longer moisture will stick around.
These creatures flourish in damp, gloomy environments, therefore if you live in a humid climate or your deck is shadowed, these variables will hasten the growth of these organisms, as they require these conditions to survive. When there is moisture present, a surface that has even accumulated pollen and other particles can become dangerously slippery.
Read more: When is the Best Time to Build a Deck or Patio?
Under the same kinds of situations that were just stated, it doesn't matter if your deck is composed of real wood or composite decking material; either one of them could potentially cause you to fall. Even though composite decks are designed to have a longer lifespan than natural wood decks, the surfaces of composite decks are not impenetrable to mold and moss, which causes the surfaces to become slippery.
Preventing Your Deck from Becoming Slippery
Regular cleaning and upkeep is the most effective method for achieving a slip-resistant deck surface, regardless of whether the surface is built of wood or composite material.
Read more: How to Build Stairs with Paver Stones
Sweep and Clear Debris
The accumulation of moisture on the surface of your deck, which can lead to the formation of mold, mildew, and algae, can be avoided by promptly cleaning leaves off of the deck. This is especially important after storms and rain. You may also prevent the growth of mold and other microorganisms by using a putty knife or another tool with a flat edge to remove debris from cracks and spaces between boards.
Read more: How to Install Composite Decking
Clean your Deck Annually
This is possibly the most crucial stage in the process of preventing a slippery surface on the deck. If you give your deck an annual deep cleaning, preferably with a power washer, the natural wood grain (or the imitation wood grain on composite decks) will be able to provide increased traction and resistance to slipping.
There are cleaning solutions that are sold commercially, or you may make your own by combining one-third of a cup of powdered laundry detergent that does not contain ammonia, one quart of bleach, and three gallons of water. To prevent the power washer from causing harm to the paint or wood stain, use a nozzle that has a broad fanning pattern.
It is possible to complete the task with either a pump sprayer or a wet-mop in the event that a power washer is unavailable. After applying the cleaning solution, let it sit there for a quarter of an hour. After that, clean the deck boards with a scrub brush that is hooked to a broom handle or a piece of wood (this makes the process much easier and faster). To complete the process, give it a thorough rinse with a hose and then let it air dry.
Read more: How to Install a Picture Frame Deck Edge
Apply Anti-Slip Products
Consider using an anti-slip solution of marine quality, such as Rust-Oleum Marine Anti-Slide Additive, if you want to add a little bit of extra slip resistance to areas that get a lot of foot traffic, steps, or other areas where safety is an issue. Sand or aggregates, which are often blended with paint or resin to offer more grip, are typically contained in this and other anti-slip solutions that are similar to it. You might also try using self-adhesive strips of coarse grit, which have the texture of a very fine grade of sandpaper but are much easier to apply.
FAQs for Preventing & Treating a Slippery Deck
Why is my deck slippery?
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A wet deck + trapped debris grows algae/mold/mildew, which reduces traction on wood and composite alike. Sweep debris routinely, then wash with soapy water to remove the biofilm.
What’s the fastest way to make a slippery deck safe today?
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Clear debris, wash the walk path, then add temporary traction where needed: adhesive grit strips on stairs/entries or a non-slip additive mixed into a compatible topcoat. (Longer term: address shade/drainage so surfaces dry faster.)
What cleaner should I use to remove algae or mildew without damaging the deck?
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Use oxygen-bleach–based cleaner or mild soap + water; scrub, then rinse. Avoid chlorine bleach on wood/composites and never mix bleach with ammonia (toxic gas).
Can I pressure-wash a composite deck to fix slipperiness?
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Yes—follow manufacturer limits. Example (Trex high-performance lines): up to 3100 psi, fan tip, keep ≥8 in (203 mm) away, and rinse each board thoroughly. Early-generation composites: avoid pressure washing.
Are composite decks slippery when wet or icy?
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Any deck can be slick when wet, and freezing weather increases slip risk. Keep surfaces clean/dry and follow winter care steps from your brand.
How do I prevent a slippery deck long-term?
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Make drying the priority: sweep leaves/pollen, clear board gaps, trim plants to boost sun/airflow, fix standing water, and schedule seasonal deep cleans. Add permanent traction where needed (e.g., non-slip coatings/strips).
What ice-melt is safe on composite decks?
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Use calcium-chloride (or rock salt per some makers) and a plastic shovel—avoid sand (abrasive). Rinse residue when practical.
Are DIY solutions like vinegar or “homemade cleaners” OK?
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Yes—manufacturer guidance allows mild DIY options (e.g., oxygen bleach solutions; white vinegar for hard-water spots). Always spot-test, protect plants, and rinse well. Again: do not mix bleach with ammonia/other cleaners
